ELISA stands for enzyme linked immunosorbent assay. In short, it is an antibody test or a test for immune response to things attacking the body such as virus, bacteria and allergens. The test is done in an ELISA plate, also known as a 96-well plate or microplate. The ELISA reader reads the plate.
What an ELISA Reader Does
ELISA readers or micro plate readers do spectrophotometry; they emit light at one wave length, and measure the amount of light absorbed and reflected by an object such as a protein. A spectrophotometer measures ultraviolet and visible light.
Additionally, ELISA plate readers can also measure fluorescence and luminescence. Chemical dyes fluoresce or emit one color or wavelength when exposed to light. The amount of reflection, absorption and the color identify, and measure the amount of a substance.
Purpose of an ELISA reader
ELISA readers were designed for measuring antibody tests. They worked so well, the machine has been adapted to other purposes. Researchers use them for protein and enzyme assays. They are also used for HIV detection and quantitation of nucleic acids.
Advantages of ELISA Reader
To use a spectrophotometer or ELISA plate reader, the molecule must be dissolved in solution. A spectrophotometer requires between 400 micro-liters and four milliliters, depending on the manufacturer and model. An ELISA plate reader needs about two to 100 micro-liters; ELISA plate readers use much less of a sample to get a result.
ELISA plate readers measure more samples in a shorter period of time. A spectrophotometer measures one to six samples at a time. Typically, an ELISA plate measures 96 wells in an equivalent amount of time.
- "Alcamo's Fundamentals of Microbiology"; 9th ed. Jeffrey C. Pommerville, 2011
- University of Arizona: Introduction to ELISA Activity
- Rice University: Spectrophotometry
- Davidson College: Spectrophotometry: Basic Principles
- cottage hospital image by Chris Bolton from Fotolia.com